
Color Modification of Spinel by Nickel Diffusion: A New Treatment
Reports on a newly discovered treatment process for producing a deep blue color in natural spinel and proposes identification criteria.

Fire Obsidian’s Beguiling Spectrum
A look at a rare volcanic glass from central Oregon with lapidary artist Tom Dodge.

Origins of Color in Brown Mammoth Ivory
Investigates the mineral and chemical compositions and surface morphology characteristics of brown mammoth ivory to identify the origins of its brown color.

Gem-Quality Augite from Dong Nai, Vietnam
Offers a comprehensive look at a variety of augite from Dong Nai, Vietnam, detailing its formation and gemological characteristics.
Gems Formed in Metamorphic Rocks
Gemstones formed in metamorphic environments offer insights into the earth’s history and the evolution of tectonic activity that led to their formation.

Spring 2023 Auction Highlights
After a slow start, the spring 2023 auction season ends with multiple broken records.

Solid Laboratory-Grown Single-Crystal Diamond Ring
The quality and size of this 4.04 ct CVD-grown diamond ring demonstrate the advancing technology in laboratory-grown diamonds.

GIA 鑑定整鑽實驗室培育鑽石戒指
GIA, the leading institute for research into diamonds, colored stones and pearls, recently evaluated a diamond ring cut from a single laboratory-grown diamond.

GIA Evaluates Solid Laboratory-Grown Diamond Ring
GIA, the leading institute for research into diamonds, colored stones and pearls, recently evaluated a diamond ring cut from a single laboratory-grown diamond.

Industry Leaders Explore Purpose and Resilience at GIA Global Leadership Program at Harvard Business School
41 leaders from every global gem and jewelry sector gathered recently for a transformative educational experience at the 2023 GIA Global Leadership Program at Harvard Business School (HBS)

Industry Leaders Explore Purpose and Resilience at GIA Global Leadership Program at Harvard Business School
41 leaders from every global gem and jewelry sector gathered recently for a transformative educational experience at the 2023 GIA Global Leadership Program at Harvard Business School (HBS)

GIA Releases First Sustainability Report
“Understanding our impact on the environment, societies and communities in which we operate is integral to our important consumer protection mission,” said GIA President and CEO Susan Jacques, speaking about the launch of the first GIA sustainability report on Friday, June 2, at the JCK Las Vegas show.

GIA Releases First Sustainability Report
“Understanding our impact on the environment, societies and communities in which we operate is integral to our important consumer protection mission,” said GIA President and CEO Susan Jacques, speaking about the launch of the first GIA sustainability report on Friday, June 2, at the JCK Las Vegas show.

Alliance for Responsible Mining and Mercury Free Mining Field Test Innovative Artisanal Gold Processing System
The recent successful field-test of an innovative system for mercury-free processing of gold ore is a significant advancement in the important effort to safeguard the health and safety and improve economic outcomes for artisanal, small-scale gold miners (ASGM) and their communities.

Quarterly Crystal: Columbite(?) in Beryl
Examination of a gem-quality aquamarine crystal reveals an inclusion cluster presumed to be columbite.

A “Flying Insect” in Diamond
A partially exposed orange garnet inclusion with surrounding fractures resembles a flying insect in a brownish yellow diamond.
Ethical Supply Chain Practices in Africa with Virtu Gem
A look at Virtu Gem, a company dedicated to improving artisanal mining practices in Africa.

Plastic Deformation: How and Why Are Most Diamonds Slightly Distorted?
A look at plastic deformation, one of the most prevalent features in natural diamond.

Microscopic Shells in Natural Pearls from Pinctada radiata
Two pearls from Bahrain containing minute shells are examined at GIA’s Mumbai laboratory.

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